High-repetition-frequency single-photon laser radar capable of eliminating distance ambiguity

Abstract

The present invention discloses a high-repetition-frequency single-photon laser radar capable of eliminating distance ambiguity, the laser radar comprises: a control module, a laser device, a beam splitter, a transmitting optical system, a photodiode, an event timer, a receiving optical system, a single photon detector, and a signal processing module. The laser radar uses the control module to generate a pulse signal with adjustable repetition frequency, and uses the pulse signal as a main control signal of the laser device to control transmission timing of the laser pulse; the laser radar uses the event timer to record pulse time of reference light and echo light respectively, and uses the signal processing module to perform time-dependent single photon counting processing. Since the laser pulse frequency is constantly changing, only the echo light pulse of current triggering moment can be accumulated during an accumulation process, the echo light pulses that are not at the current triggering moment is discretized, and eventually, the single-photon laser radar can eliminate the distance ambiguity problem under high repetition frequency conditions.

Description

technical field [0001] The invention belongs to the technical field of laser radar, in particular to a high-repetition-frequency single-photon laser radar capable of eliminating distance ambiguity. Background technique [0002] Single-photon lidar uses single-photon detectors to receive photon-level echo signals, and uses Time-Correlated Single Photon Counting (TCSPC) technology to improve the detection sensitivity of optical signals for time-of-flight ranging to the quantum limit. Greatly increased the range of lidar. Although single-photon lidar has high detection sensitivity, the TCSPC technology it uses requires multiple accumulations to extract the distance information of the target. Under the condition of a certain repetition frequency, increasing the cumulative number of times will cause the ranging time to be too long, which cannot be applied to the laser ranging occasion of the moving target. Therefore, increasing the repetition rate of laser pulses is an effectiv...

AI Technical Summary

Problems solved by technology

However, the problem with this approach is that the dead time of the single-photon detector reduces the correlation between the transmitted pulse and the echo pulse, thereby reducing the sensitivity of echo detection.

However, when the time interval between two adjacent echo signals is very short (less than the dead time of the single photon detector), the dead time of the single photon detector will affect the detection probability of the echo echo signal

Images